The present invention relates generally to a seat construction and in particular to an attachment of a suspension mat to a tubular seat frame.
One way of constructing a seat, such as a vehicle seat, home furniture seat or lawn furniture seat, is to provide a structural frame upon which a seat suspension mat is supported. The suspension mat can then be used to support a resilient foam pad, or alternatively, the suspension mat can be used as the seating surface. This eliminates the need for a foam cushion and provides a lightweight and low cost seat. One example of a seat in which an occupant sits directly on a suspension mat is a director's chair. A director's chair includes a lightweight folding frame with a woven material spanning across the frame upon which a person sits. A variety of materials can be used for the frame including wood, metal, plastic composites, etc.
Metal tubing is a desirable frame material, especially when the frame will be bent in multiple directions. Metal tubing can easily be bent in multiple directions because its bending characteristics are similar regardless of which direction it is bent. Attachment of the suspension mat to a tubular frame is sometimes accomplished by a plurality of screws along the sides of the mat. Additional reinforcements for the mat may also be required at the point of attachment such as eyelets at the screw holes or a wire or rib sewn into a hem along the edge of the mat.
It is an object of the present invention to provide an improved and simplified attachment of a suspension mat to a tubular seat frame.
The suspension mat attachment of the present invention utilizes a J-clip fastener attached to the edge of the suspension mat. At the location where the J-clip fastener is attached to the tube, the tube is formed inward over a portion of the tube circumference. This produces a concave tube surface portion. The J-clip fastener is configured to match the shape of the tube and engages both the concave, formed tube portion, and the convex, non-formed tube portion. By forming the tube where the J-clip fastener is attached, the J-clip fastener can be attached in a manner that precludes rotation of the fastener about the tube axis. By preventing rotation of the fastener about the tube, the mat remains in a fixed position and with a known amount of tension. The amount of tube deformation or forming is dependent upon the material, diameter and wall thickness of the tube and the strength requirements for the seat frame. The suspension, once attached to the tube, can be used as the primary seating surface or it can be used to support an upholstered foam pad.
The invention is broadly defined as a seat assembly including a support frame having a tubular member with a cylindrical surface which has an attaching section in which the tubular member is formed about a portion of its cylindrical surface producing a concave surface portion and a convex surface portion with a bent edge therebetween. A suspension mat is attached to the tubular member at the attaching section. The suspension mat is attached by a fastener that is coupled to the suspension mat and has a generally hook shaped configuration to engage the attaching section of the tubular member and wrap around and cover the bent edge of the tubular member.
Further objects, features and advantages of the invention will become apparent from a consideration of the following description and the appended claims when taken in connection with the accompanying drawings.